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In the process of repairing the surface of products in aviation, aerospace, and other fields by spraying, accurate 3D cumulative-coating modeling is an important research issue in spraying-process simulation. The approach to this issue is a 3D cumulative-coating model based on inclined spraying. Firstly, an oblique spraying layer cumulative model was established, which could quickly collect the coating thickness distribution data of different spray distances. Secondly, 3D cumulative-coating modeling was conducted with the distance between the measuring point and the axis of the spray gun and the spraying distance between the measuring points as the input parameters, and the coating thickness of the measuring point as the output parameter. The experimental results show that the mean relative error of the cumulative model of the oblique spraying layer is less than 4.1% in the case of a 170~290 mm spraying distance and that the model is applicable in the range of -80~80 mm, indicating that the data on the oblique spraying coating proposed in this paper is accurate and fast. The accuracy of the 3D cumulative-coating model proposed in this paper is 1.2% and 21.5% higher than that of the two similar models, respectively. Therefore, the approach of 3D cumulative-coating modeling based on inclined distance spraying is discovered, demonstrating the advantages of fast and accurate modeling and enabling accurate 3D cumulative-coating modeling for spraying process simulation.
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Fatigue and stress are critical variables that impair railway train drivers' safety performance, and individual differences may influence these effects. This study investigates how fatigue and stress affect high-speed train drivers' human error and the role of individual differences. We hypothesised that situation awareness (SA) mediates the effects of fatigue and stress on human error, and individual differences (age and work experience) moderate these effects. We surveyed 1,391 male drivers from eight Chinese railway bureaus and used PROCESS Macro for data analysis. The results revealed that fatigue and stress increased human error, directly and indirectly through SA. Age and work experience moderated the effect of fatigue and stress on SA, respectively. Older drivers had better SA under high fatigue, while more experienced drivers had better SA under high stress. These findings can inform more tailored safety management strategies to lower human error and enhance the safety of high-speed train operations.
A cross-sectional survey of 1,391 high-speed train drivers in China indicated that fatigue and stress amplify human error by impairing situation awareness (SA). Age and work experience were observed to moderate the impact of fatigue and stress on SA, respectively. These insights guide the advancement of safety management strategies.
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Porous-structured evaporators have been fabricated for achieving a high clean water throughput due to their maximized surface area. However, most of the evaporation surfaces in the porous structure are not active because of the trapped vapor in pores. Herein, a three-dimensional (3D) cylindrical aerogel-based photothermal evaporator with a disordered interconnected hierarchical porous structure is developed via a Pickering emulsion-involved polymerization method. The obtained cotton cellulose/aramid nanofibers/polypyrrole (CAP) aerogel-based evaporator achieved all-cold evaporation under 1.0 sun irradiation, which not only completely eliminated energy loss via radiation, convection, and conduction, but also harvested massive extra energy from the surrounding environment and bulk water, thus significantly increasing the total energy input for vapor generation to deliver an extremely high evaporation rate of 5.368 kg m-2 h-1 . In addition, with the external convective flow, solar steam generation over the evaporator can be dramatically enhanced due to fast vapor diffusion out of its unique opened porous structure, realizing an ultrahigh evaporation rate of 18.539 kg m-2 h-1 under 1.0 sun and 4.0 m s-1 . Moreover, this evaporator can continuously operate with concentrated salt solution (20 wt.% NaCl). This work advances rational design and construction of solar evaporator to promote the application of solar evaporation technology in freshwater production.
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The elimination of S-containing compounds in heavy oil is of significant importance to viscosity reduction and oil quality elevation in order to enhance oil recovery. In this study, the decomposition behavior of S-containing compounds in heavy oil was elucidated from a theoretical perspective in conjunction with simulative experiments. CH3SCH3 was employed as a model molecule on behalf of straight-chain saturated sulfides in heavy oil. The common cost-friendly inverse spinel Fe3O4 was selected as the catalyst. Our theoretical calculations revealed that the most feasible reaction pathway of entire CH3SCH3 decomposition occurred in two steps with the assistance of weakly adsorbed H2O molecules, generating two CH3OH molecules and one H2S molecule, of which the first step was the rate-determining step. These calculated results were confirmed with experimental results, which contributed to a clear and reliable catalytic desulfurization mechanism for S-containing compounds in heavy oil during aquathermolysis.
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OBJECTIVE: This study used electroencephalography to explore the behavioral and electrophysiological effects of task interruption on performance. BACKGROUND: Task interruption is known to harm work performance, especially on working memory-related tasks. However, most studies pay little attention to cognitive processes by exploring brain activity and ignore the cumulative effect of sequential interruptions. METHOD: Thirty-four healthy participants performed a spatial 2-back in three conditions: (1) interruptions with simple math questions, (2) suspensions with prolonged fixation cross, and (3) a pure 2-back. The measured outcomes comprise performance data, ERP amplitudes, EEG power, and subjective workload. RESULTS: Work performance decreased in the resumption trials, and cumulative interruptions had a more destructive effect on performance. EEG results showed that the P2 and P3 amplitudes induced by the 2-back task significantly increased after interruptions; theta and alpha power increased after interruptions. The P3 amplitude and alpha power induced by interruptions were significantly higher than that induced by suspensions. CONCLUSION: Behavioral data revealed the disruptive effect of interruptions on postinterruption performance and the cumulative effect of interruptions on accuracy. Changes in ERP amplitudes and EEG power indicate the mechanisms of attention reallocation and working memory during interruptions. Larger P3 amplitudes and alpha power after interruptions than after suspensions suggested the inhibition of irrelevant information. These results may support the memory for goals model and improve the understanding of the effects of interruption on working memory. APPLICATION: Focusing upon the mechanisms at play during the interruption process can support interruption management to ensure work safety and efficiency.
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Due to the diversity of sulfur valence in cobalt-based sulfides, it is difficult to control the crystal phase and composition of the products during synthesis. Herein, a one-pot hydrothermal method is reported to self-assemble the cobalt sulfides (CoS2, Co9S8and Co3S4) with hollow nanostructures. The whole preparation process is simple and mild, avoiding high temperature calcination. The performances of the three kinds of cobalt sulfide in superior supercapacitors and electrocatalytic oxygen evolution performance applications follow the order of CoS2 > Co9S8 > Co3S4. Further analysis demonstrates that the performance difference in these cobalt sulfides may be attributed to three factors: the presence ofS22-,the coordination environment of Co and the presence of continuous network of Co-Co bonds. The distinctive electrochemical performance of CoS2and Co9S8may help us to better understand the excellent electrochemical activity of metal polysulfides and metal sulfides after doping or alloying. Therefore, this work may provide a reference in understanding and designing the electrode materials for highly efficient applications in the fields of energy storage and conversion.
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Trophoblast cell-surface antigen 2 (Trop 2) is a transmembrane glycoprotein that is highly expressed in various cancer types with relatively low or no baseline expression in most normal tissues. Its overexpression is associated with tumor growth and poor prognosis; Trop 2 is, therefore, an ideal therapeutic target for epithelial cancers. Several Trop 2 targeted therapeutics have recently been developed for the treatment of cancers, such as anti-Trop 2 antibodies and antibody-drug conjugates (ADCs), as well as Trop 2-specific cell therapy. In particular, the safety and clinical benefit of Trop 2-based ADCs have been demonstrated in clinical trials across multiple tumor types, including those with limited treatment options, such as triple-negative breast cancer, platinum-resistant urothelial cancer, and heavily pretreated non-small cell lung cancer. In this review, we elaborate on recent advances in Trop 2 targeted modalities and provide an overview of novel insights for future developments in this field.
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Moléculas de Adesão Celular/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Antígenos de Neoplasias/química , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/fisiologia , Moléculas de Adesão Celular/química , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/fisiologia , Humanos , Imunoconjugados/uso terapêutico , Imunoterapia AdotivaRESUMO
With the improvement in automation technology, humans have now become supervisors of the complicated control systems that monitor the informative human-machine interface. Analyzing the visual attention allocation behaviors of supervisors is essential for the design and evaluation of the interface. Supervisors tend to pay attention to visual sections with information with more fuzziness, which makes themselves have a higher mental entropy. Supervisors tend to focus on the important information in the interface. In this paper, the fuzziness tendency is described by the probability of correct evaluation of the visual sections using hybrid entropy. The importance tendency is defined by the proposed value priority function. The function is based on the definition of the amount of information using the membership degrees of the importance. By combining these two cognitive tendencies, the informative top-down visual attention allocation mechanism was revealed, and the supervisors' visual attention allocation model was built. The Building Automatic System (BAS) was used to monitor the environmental equipment in a subway, which is a typical informative human-machine interface. An experiment using the BAS simulator was conducted to verify the model. The results showed that the supervisor's attention behavior was in good agreement with the proposed model. The effectiveness and comparison with the current models were also discussed. The proposed attention allocation model is effective and reasonable, which is promising for use in behavior analysis, cognitive optimization, and industrial design.
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Purpose: The pericapsular nerve group (PENG) block provides satisfactory postoperative analgesia without hampering motor function for total hip arthroplasty (THA); however, unexpected motor block has been observed clinically. It is unknown whether this motor block is related to the dose of ropivacaine. We aimed to conduct a prospective randomized trial to test whether reducing the volume or concentration of ropivacaine was better for less motor block after PENG block. Patients and Methods: Ninety-nine patients with fracture or femoral head necrosis scheduled for THA were randomly allocated to receive 20 mL 0.5% ropivacaine (Group A), 20 mL 0.25% ropivacaine (Group B), and 10 mL 0.5% ropivacaine (Group C). The primary outcome was the incidence of postoperative quadriceps motor block at 6 hours. Secondary outcomes were the incidence of postoperative quadriceps motor block at 0, 12, 24 and 48 hours; pain scores on the numeric rating scale (NRS) at all postoperative time points (0, 6, 12, 24, and 48 hours); the time to first walk; the incidence of rescue analgesia; side effects such as dizziness, ache, nausea, and vomiting; and patient satisfaction. Results: Compared with Group A, Group C resulted in a lower incidence of quadriceps motor block at 0 hours, 6 hours and 12 hours postoperatively (P < 0.05), while Group B only resulted in a lower incidence of motor block at 12 hours postoperatively (P < 0.05). No intergroup differences were found in terms of postoperative pain scores, the incidence of rescue analgesia, adverse events or patient satisfaction (P > 0.05). Conclusion: A higher incidence of motor blockade was observed when 20 mL of 0.5% ropivacaine was administered, which was mainly caused by the excessive volume. Therefore, we recommend performing PENG block with 10 mL 0.5% ropivacaine.
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The zinc-air battery (ZAB) performance and stability strongly depend on the structure of bifunctional electrocatalyst for oxygen reduction/evolution reaction (ORR/OER). In this work, we combine the tip and heterogeneous effects to construct cobalt/cobalt oxide heterostructure nanoarrays (Co/CoO-NAs). Due to the formed heterostructure, more oxygen vacancies are found for Co/CoO-NAs resulting in a 1.4-fold higher ORR intrinsic activity than commercial carbon supported platinum electrocatalyst (Pt/C) at 0.8 V versus reversible hydrogen electrode (vs. RHE). Moreover, a fast surface reconstruction is observed for Co/CoO-NAs during OER catalysis evidenced by in-situ electrochemical impedance spectroscopy and Raman tests. In addition, the tip effect efficiently lowers the mass transfer resistance triggering a low overpotential of 347 mV at 200 mA cm-2 for Co/CoO-NAs. The strong electronic interplay between cobalt (Co) and cobalt oxide (CoO) contributes to a stable battery performance during 1200 h galvanostatic charge-discharge test at 5 mA cm-2. This work offers a new avenue to construct high-performance and stable oxygen electrocatalyst for rechargeable ZAB.
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We report the synthesis of nanoporous Cu/Ag bimetallic triangular nanoprisms (BTNPs) using a galvanic replacement method. Based on ultraviolet-visible spectroscopy (UV-vis), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), X-ray diffraction (XRD), energy dispersive spectrometry (EDS), selected area electron diffraction (SAED) and X-ray photoelectron spectroscopy (XPS) analyses, the structure of Cu/Ag BTNPs was characterized. The prepared Cu/Ag BTNPs exhibited excellent catalytic activity and good cycling stability for the reduction of 4-nitrophenol (4-NP) due to the synergistic effect between Cu and Ag elements. The kinetic rate constant (k) and turnover frequency (TOF) values reached 331 × 10-3 s-1 and 500 × 10-3 s-1, respectively, which were higher than those of previously reported Cu, Ag, Au, Cu/Ag or Cu/Au-based catalysts. We hope that the development of promising routes for high-quality BTNPs can broaden their applications in catalysis and environmental sustainability.
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Dendrite growth and parasitic reactions with liquid electrolyte are the two key factors that restrict the practical application of the lithium metal anode. Herein, a bis(benzene sulfonyl)imide based single-ion polymer artificial layer for a lithium metal anode is successfully constructed, which is prepared via blending the as-prepared copolymer of lithiated 4, 4'-dicarboxyl bis(benzene sulfonyl)imide and 4,4'-diaminodiphenyl ether on the surface of lithium foil. This single-ion polymer artificial layer enables compact structure with unique continuous aggregated Li+ clusters, thus reducing the direct contact between lithium metal and electrolyte simultaneously, ensuring Li+ transport is fast and homogeneous. Based on which, the coulombic efficiency of the Li|Cu half-cell is effectively improved, and the cycle stability of the Li|Li symmetric cell can be prolonged from 160 h to 240 h. Surficial morphology and elemental valence analysis confirm that the bis(benzene sulfonyl)imide based single-ion polymer artificial layer effectively facilitates the Li+ uniform deposition and suppresses parasitic reactions between lithium metal anode and liquid electrolyte in the LFP|Li full-cell. This strategy provides a new perspective to achieve a steady lithium metal anode, which can be a promising candidate in practical applications.
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Exploring efficient, stable and multifunctional Earth-rich electrocatalysts is vital for hydrogen generation. Hence, an efficient heterostructure consisting of cauliflower-like NiFe alloys anchored on flake iron nickel carbonate hydroxide which is supported on carbon cloth (NiFe/NiFeCH/CC) was synthesized as a trifunctional electrocatalyst for efficient hydrogen production by overall water and urea splitting. While optimizing and regulating the ratio of Ni to Fe, benefiting from the special morphology and synergistic effect between the NiFe alloy and NiFeCH, the NiFe/NiFeCH/CC heterostructure exhibits outstanding oxygen evolution reaction (OER) performance with a low overpotential of 190 mV at 10 mA cm-2 after a stability test for 150 h. Notably, when the NiFe/NiFeCH/CC heterostructure is used as both the anode and cathode simultaneously, it merely requires a cell voltage of 1.49 V for the overall water splitting and 1.39 V for urea electrolysis at 10 mA cm-2 with excellent durability. Thus, this work not just provides the application of NiFe-based catalysts in overall water splitting, but also offers a viable method for the treatment of urea-rich wastewater.
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Water splitting, an efficient technology to produce purified hydrogen, normally requires high cell voltage (>1.5 V), which restricts the application of single atoms electrocatalyst in water oxidation due to the inferior stability, especially in acidic environment. Substitution of anodic oxygen evolution reaction (OER) with hydrazine oxidation reaction (HzOR) effectually reduces the overall voltage. In this work, the utilization of iridium single atom (Ir-SA/NC) as robust hydrogen evolution reaction (HER) and HzOR electrocatalyst in 0.5 m H2 SO4 electrolyte is reported. Mass activity of Ir-SA/NC is as high as 37.02 A mgIr -1 at overpotential of 50 mV in HER catalysis, boosted by 127-time than Pt/C. Besides, Ir-SA/NC requires only 0.39 V versus RHE to attain 10 mA cm-2 in HzOR catalysis, dramatically lower than OER (1.5 V versus RHE); importantly, a superior stability is achieved in HzOR. Moreover, the mass activity at 0.5 V versus RHE is enhanced by 83-fold than Pt/C. The in situ Raman spectroscopy investigation suggests the HzOR pathway follows *N2 H4 â*2NH2 â*2NHâ2Nâ*N2 âN2 for Ir-SA/NC. The hydrazine assisted water splitting demands only 0.39 V to drive, 1.25 V lower than acidic water splitting.
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In a concurrent multitasking environment, performing many types of tasks increases task complexity, and working long hours makes a person susceptible to mental fatigue. Emerging technologies may lead to more task interruptions. This study examines the effects of task attributes and mental fatigue on interrupted task performance in a concurrent multitasking environment. Thirty-four participants performed the MATB-â ¡ under eight conditions (two-level task interruption, two-level task complexity, two-level fatigue). The results revealed the significant interaction effects of interruption × task complexity and of interruption × fatigue state. The findings show that more time is required to return to a complex primary task, and there are differences among subtask types. Mental fatigue negatively affects primary task performance, workload, and the resumption lag after an interruption. The findings are explained by the increasing information cues needed to resume complex tasks and the negative effect of fatigue on memory activation.
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Análise e Desempenho de Tarefas , Carga de Trabalho , Humanos , Fadiga Mental/etiologiaRESUMO
The development of earth-abundant catalysts toward high-efficiency overall water splitting is of critical importance for electrochemical hydrogen production. Here, novel FeNi alloy quantum dot (QD)-decorated cobalt carbonate hydroxide (CoCH) nanosword arrays were successfully constructed on Ni foam (FeNi/CoCH/Ni foam) and used as an efficient bifunctional electrocatalyst for overall water splitting in alkaline media. Benefiting from the synergistic effect between the FeNi alloy QDs and CoCH, the FeNi/CoCH/Ni foam electrode delivers a current density of 20 mA cm-2 at an overpotential of 240 mV and a small Tafel slope of 44.8 mV dec-1 for the oxygen evolution reaction (OER). Further, it displays excellent performance for overall water splitting with a voltage of 1.49 V at 10 mA cm-2 and maintains its activity for at least 23 h. In particular, it only needs low cell voltages of 1.54 and 1.6 V to drive high current densities of 100 and 400 mA cm-2, respectively, which is much better than commercial Pt/C/Ni foamâRuO2/Ni foam, providing great potential for large-scale application.
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Interruption generally has a negative effect on performance by affecting working memory (WM). However, the neural mechanism of interruption has yet to be understood clearly, and previous studies have largely ignored the role of fatigue state. To address these issues, the present study explores the behavioral and electrophysiological effects of interruption on WM performance using electroencephalography (EEG) data. The moderating effect of fatigue is also explored. The participants performed spatial 2-back tasks with math task interruption, suspension interruption, and non-interruption under different fatigue states. The results show that interruption led to increased alpha activity and P300 amplitude, indicating inhibitory control to interference from irrelevant information. Analysis of P200 amplitude revealed that interruption affected attentional reallocation when resuming the primary task. Increased theta power indicated an increased demand for information maintenance during the interruption. A speeding-up effect was discovered after interruption; however, fatigue impaired cognitive ability and further exacerbated the negative effects of interruption on WM and behavioral performance. These findings contribute to a better understanding of cognitive activity during the interruption and of the interaction with fatigue, and provide further support for the theory of memory for goals (MFG).
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Although noble metal or non-noble metal-catalyzed reactions are widely used, it is still difficult to apply these reactions in the large-scale synthesis of chemicals because most of the reactions are carried out by the inefficient batch reaction strategy. Herein, Pickering emulsion-based continuous flow catalysis was utilized to address this problem. Cellulose nanofibers with aldehyde groups (ACNF) were generated through oxidizing C2 and C3 hydroxyl groups of cellulose nanofibers into aldehyde groups by NaIO4, followed by in situ depositing Ag nanoparticles on ACNF to produce Ag-decorated ACNF (ACNF@Ag) via a facile aldehyde-induced reduction method. ACNF@Ag with â¼2 wt % Ag (ACNF@Ag2) has been used to prepare the Pickering emulsion by controlling the electrostatic interaction between ACNF@Ag2 and the oil-water interface via adjusting the pH. It was found that the Pickering emulsion could be generated at a pH around 3.29 and was determined to be the oil-in-water emulsion. The reduction of organic molecules (4-nitrophenol (4-NP), methylene blue (MB), and methyl orange (MO)) was selected as a model reaction to test the reliability of the Pickering emulsion in continuous flow catalysis, which demonstrated very high conversion rates for 4-NP (>98%, 50 h), MB (>99%, 30 h), and MO (>96%, 40 h).
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Diabetes exacerbates brain damage in cerebral ischemic stroke. Our previous study has demonstrated that after cerebral ischemia, type 2 diabetes rats displayed worse neurological outcomes, larger cerebral infarction and severer blood-brain barrier disruption. However, our knowledge of the mechanisms of how diabetes impacts the cerebrovascular repair process is limited. This study was aimed to characterize structural alterations and potential mechanisms in brain microvessels before and after ischemic stroke in type 2 diabetic rats treated with high-fat diet and streptozotocin (HFD/STZ). Furtherly, we tested our hypothesis that dysregulated intercellular Jagged1-Notch1 signaling was involved in the dysfunctional cerebral neovascularization both before and after ischemic stroke in HFD/STZ rats. In our study, we found increased yet dysfunctional neovascularization with activated Jagged1-Notch1 signaling in the cerebrovasculature before cerebral ischemia in HFD/STZ rats compared with non-diabetic rats. Furthermore, we observed delayed angiogenesis as well as suppressed Jagged1-Notch1 signaling after ischemic stroke. Our results elucidate the potential mechanisms underlying diabetes-related cerebral microvasculature dysfunction after ischemic stroke.
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Mesoporous silica encapsulating upconversion luminescence NaYF(4) nanorods with uniform core-shell structures have been successfully synthesized by the surfactant-assistant sol-gel process. The thickness of ordered mesoporous silica shells can be adjusted from 50 to 95 nm by varying the amount of hydrolyzed silicate oligomer precursors from tetraethyl orthosilicate (TEOS), which further influences the BET surface area, pore volume, and the luminescence intensity. After coated with mesoporous silica shells, the hydrophobic nanorods is rendered to hydropholic simultaneously. The obtained beta-NaYF(4)@SiO(2)@mSiO(2) core-shell nanorods possess high surface area (71.2-196 m(2) g(-1)), pore volume (0.07-0.17 cm(3) g(-1)), uniform pore size distribution (2.3 nm), and accessible channels. Furthermore, the uniform core-shell nanorods show strong upconversion luminescence property similar to the hexagonal upconversion cores. The open mesopores can not only provide convenient transmission channels but also offer the huge location for accommodation of large molecules, such as fluorescent dyes and quantum dots. The secondary-excitation fluorescence of Rhodamine B is generated from the upconversion rare-earth fluoride nanorods cores to the fluorescent dyes loaded in the mesoporous silica shells.